Hydraulic fishing tool



June 28, 1949. J. A. ARMITAGE 2,474,453

' aynnwmc FISHING TOOL Filed Aug. 2, "1948 2 Sheets-Sheet 1 liI l /A $92$22 vmw FIG. 2

A TTORNE Y June 28, 1949. J. A. ARMITAGE HYDRAULIC FISHING TOOL FiledAug. 2, 1948 2 Sheets-Sheet 2 P 1 u wm sig u m 1H Willeli'll I-VVENTQR.BY JM IL ATTORNEY Patented June 28, 1949 UNITED STATES PATENT OFFICE vn-Ymuimc msnmc 'rooL I A. Armitag e, Houston, Tex. ADDlicationAugust 2,1948, Serial No. 42,017

' a ciaimsJwL'm-mm It is a further object of the invention to prowide afishing tool of the characterdescribed which may be engaged with thestuck object and successively operated to exert successive pulls on theengaged object until said object has been released to be withdrawn tothe ground surface. Other objects and advantages will be apparent fromthe following specification which is illustrated by the accompanyingdrawings, wherein:

Figure 1 is a vertical, sectional view of the lower end. of the toolwhile being lowered into operative position.

Figure 2 is a vertical, sectional view of the upper end thereof.

Figure 3 is a cross-sectional view taken on the line 3-3 of Figure 1. v

Figure 4 is a vertical, sectional view of the lower end of the toolengaged with the well casing and in operative position. I

Figure 5 is a vertical, sectional view of the upper end thereof, and

Figure 6 is a side elevation of the complete tool in operative positionin the well casing and shown engaged with the object to be removed.

Referring now more particularly to the drawings wherein like numerals ofreference designate the same parts in each of the figures, the numeral Idesignates the operating string which is of tubular formation and whichextends to the ground surface.

Connected to the lower end of this string there is a tubular mandrel 2whose lower end is provided with a valve seat which is controlled by anupwardly opening valve 4.

Connected to the lower end of the mandrel 2 there is a grapple 5 of anyselected type and which is engageable with the stuck object 6.

Secured on the upper end of the mandrel there is a disc 1 which isclamped between the lower end of the operating string I and a supportingshoulder 8 on said mandrel and secured on the lower end of the mandrelthere is a disc 9 which is clamped between the upper end of the grapple5 and the downwardly facing shoulder ID on the mandrel.

The numeral ll designates a cylinder whose lower end is provided withdownwardly converging tapering faces l2 and slidably mounted on thesefaces and having dovetailed connections therewith there are the wedgeshaped slips ll whose outer surfaces are provided with downwardlypitched teeth which are engageable with the well casing when in' theposition illustrated in Figure 4.

The lower end of the cylinder II is closed and is provided with aconventional stufling box ll around the mandrel 2 and screwed into theupper end of the cylinder there is a cylinder head, or plug, ii in whicha stufling box I6 is mounted which surrounds the mandrel.

The lower end of the cylinder has a ring ll welded thereto and this ringis provided with the seats III in its upper face to receive coilsprings, as H.

When the tool is in inoperative position, as shown in'Figures 1 and 2,to be lowered into the well the slips are held in their lower, orinoperative, position, by means of the rods 20 which are attached, attheir lower ends, to the disc' 9. and at their upper ends to therespective slips thus maintaining the springs l9 under compression.

The lower end of the cylinder also has passageways 2| extending upwardlyfrom the lower end of the cylinder and terminating within said lower endand these passageways have lateral ports 22 and ducts 23 leadingtherefrom and terminating within the cylinder adjacent said lower end.

Located within each passageway 2| there is a piston type valve 24 whichis mounted on a valve stem 25 whose upper end is extended up into thecylinder H and whose lower end is extended beneath said cylinder. Thelower extended end of the rod is of reduced diameter so as to provideclearance whereby the liquid beneath the cylinder H may pass upwardlythrough the passageway 2|, port 22 and passageway 23 when the valve 24is in its upper position. when said piston valve is moved to its lowerposition the passage- Y way 2| will be closed. The cylinder head 15 iswhich is reciprocable through the piston head it and whose lower endextends beneath said piston head and whose upper end extends above thepiston head.

The upper end of each piston rod '30 is reduced in diameter so as toallow clearance to the end that when the valve 29 is in its lower oropen position liquid may flow from within the cylinder through thepassageway 26, the port 21 and the passageway 28 and into the wellcasing above.

On the mandrel 2 within the cylinder N there is a piston 3| which is insealed relationship with the walls of the cylinder.

As stated the mandrel is tubular and leading from the passagewaytherethrough laterally through the piston 3| there are passageways, as32, whose outer ends terminate in bores 33 whose lower ends extendbeneath the corresponding passageways 32 and screwed into whose upperends there are the tubular plugs 34.

Fitted within each bore 33 there is a double acting valve 35 which isfixed on a valve stem 38. One end of this'stem works through an axialpassageway in the plug 34 and extends'beyond the piston 3| and the otherend of the stem works 4 through a passageway in the piston 3| andextends beyond said passageway. These passageways are larger than thestem so as to provide suflicient clearance for the flow of liquidtherethrough.

At opposite ends of each bore 33 there are the seats 31, 38 againstwhich the valve seats, alternately, to alternately open and close saidrespective passageways.

When the equipment is assembled to be lowered into the well the slips l3are held in their lower, or inactive, position by means of the rods 20and as the tool is lowered into the well the valves 4 will open to allowthe entrance of the well liquid into the mandrel 2. Each valve 24 willalso be open to allow the passage of liquid into the cylinder beneaththe piston 3| and each valve 35 will be seated beneath the correspondingpassageway 32 to allow the liquid to pass through the piston 3| and intothe cylinder above it. The tool may be lowered on down until the grapple5 is in position to engage the stuck object 5. As illustrated thisgrapple consists of a threaded tapering tap which may be screwed intothe stuck object 6; however, any conventional type of grappling tool maybe used.

Upon engagement of the grapple with the stuck object liquid may beforced under pressure down through the operating string of pipe andthrough the mandrel and out through passageways 32 and thence up throughthe passageways through the plugs 34 into the space between the piston3| and the cylinder head |5.

It will be noted from an inspection of Figure 2 that when in thisposition the valve 35 will be held in their lower position to clear thepassageways 32 by reason of the contact of the upper ends of stems 36with said head l5 and the valves 29 will be held in upper position toclose the ports 21 by reason of the contactof the piston 3| with thelower ends of the piston rods 30.

The pressure of the liquid will therefore move the cylinder ll upwardlyand the rods 20 will be broken thus freeing the springs I9 and the slips|3 will be forced upwardly into contact with the well casing, as shownin Figure 4, so as to support the tool. The cylinder II will be therebyanchored against downward movementbut will be permitted to move upwardlyand upon a continuation of said pressure the cylinder II will be movedupwardly. Eventually the upper end of each piston rod 30 will contactwith the disc 1 whereupon the piston valves 23 will be moved downwardly,as shown in Figure 5, to open the ports 21; the lower end of thecylinder will approach the piston 3| and the upper end of each pistonrod 25 will contact said piston and move the piston valve 24 downwardlyto close the port 22. as shown in Figure 4. At the same time the lowerend of each piston rod 36 will be contacted by the lower end of thecylinder, as shown in Figure 4, and the corresponding valve 35 will belifted to clear the corresponding passageway 32 and to close thepassageway above through the plugs 34.

Pressure will now be admitted into the space between the piston 3| andthe lower end of cylinder and said cylinder being anchored againstdownward movement, the piston and the mandrel 2 will be forced upwardlythus exerting a pull on the stuck object 6 and moving said objectupwardly until the piston 3| reaches the upper end of said cylinder thusreversing the position of the valves 23 and 35, as indicated in Figure 2and at the same time the position of the valve 24 will be reversed bythe disc 9 coming into contact with the lower end of the piston rods 25thus opening the port 23.

The pressure of the operating fluid will now be between the cylinderhead or plug l5 and the piston 3| and the cylinder may be again forcedupwardly, the liquid in the cylinder beneath the piston 3| beingrelieved through the ducts 23 and passageways 2|.

If a single pull does not release the stuck object, the cycle ofoperation may be repeated, if necessary, thus exerting successive pullson the stuck object until it has been dislodged.

It is to be understood, of course, that as the stuck object is movedupwardly, by successive pulls, the fishing tool as a whole, includingthe operating string I, will be elevated relative to the well casing.

What I claim is:

1. A fishing tool comprising, a tubular operating string of pipeincluding a mandrel, a cylinder through which the mandrel works andforming a closed chamber about the mandrel, a piston on the mandrel andfitted in the cylinder, the piston having a passageway for fluid leadingfrom within the string and terminating in the chamber on opposite sidesof the piston and the cylinder having fluid passageways through it'sends, valves arranged to control the, piston and cylinder passagewaysand means for reversing the position of all of said valves, when thepiston reaches the limit of its movement in either direction.

2. A fishing tool comprising, a tubular operatingstring of pipeincluding a mandrel, a cylinder through which the mandrel works andforming a closed chamber about the mandrel, a piston on the mandrel andfitted in the cylinder, the piston having a passageway for fluid leadingfrom within the string and terminating in the chambers on opposite sidesof the piston and the cylinder having fluid passageways through itsends, valves arranged to control the piston and cylinder passageways andmeans for reversing the position of all. of said valves, when the pistonreaches the limit of its movement in either direction to apply pressureto one side of the piston and simultaneously relieve the pressure fromthe other side of the piston alternately.

works and which forms a closed chamber about the mandrel, a piston onthe mandrel and fitted in the cylinder, said piston having a passagewayfor fluid leading from within the string and terminating in the cylinderchamber on opposite sides of the piston, the cylinder having 'fiuidpassageways through its ends to allowdis'charge of fluid from within thecylinder in advance of the piston, valves controllin said cylinderpassageways and means for reversing the position of all of said valves,when the piston reaches the limit of its movement in either direction.

4. A fishing tool comprising'a tubular operating stringof. pipeincluding a mandrel, means on the lower. ,end of the mandrel forengaging an object stuck in a well, a cylinder through which the mandrelworks and forming a closed chamber about the mandrel, a piston on themandrel and fitted in the cylinder, the piston having a Dassageway forfluid leading from within the string and terminating in the chamber onopposite sides of the piston and the cylinder having fluid passagewaysthrough its ends, valves arranged to control the piston and cylinderpassageways; means for reversing the position of all of said valves,when the piston reaches the limit of its movement in either directionand, grappling means on the cylinder engageable with the walls of a welland shaped to allow upward movement of the cylinder but to preventdownward movement of the cylinder. i

5. A fishing tool for wells comprising, a tubular operating string ofpipe including a mandrel, a grapple on the lower end thereof, a cylinderthrough which the mandrel works andforming a closed chamber about themandrel, wall engaging means on the cylinder-arranged to preventdownward movement of the cylinder, but to allow upward movement thereof,a piston on the mandrel and fitted in the cylinder, the piston having apassageway for fluid leading from within the string and terminating inthe chamber on op-' posite sides of the piston and the cylinder havingfiuid passageways through its ends, Valves arranged to control thepiston and cylinder passageways and means for reversing the position ofall of said valves, when the piston reaches the limit of its movement ineither direction to apply pressure to one side of the piston andsimultaneously relieve the pressure from the other side of the pistonalternately.

6. A fishing tool for wells comprising, a tubular operating string ofpipe which includes a tubular mandrel, a cylinder through which themandrel I v the mandrel, a piston on the mandrel and fitted in thecylinder, means for applying fluid, under pressure, from the string intothe cylinder on the opposite sides of the piston, alternately, means onthe cylinder engageable with the walls of the well and adapted to allowonly upward movement of the cylinder, the cylinder having fluidpassageways at its ends to allow relief of fluid from within thecylinder in advance of the piston, means automatically controlling theapplication and relief of said pressure, means for reversing theposition of the controlling means, when the piston reaches the limit ofits movement in either direction and a grapple on the mandrel engageablewith an object stuck in the well.

7. 'A fishing tool comprising, a tubular operating string of pipeincluding a mandrel, means on the lower endof the mandrel for engagingan object stuck, in a well, a cylinder through which the mandrel worksand forming a closed chamberabout the mandrel, a piston on the mandreland fitted in the cylinder, means for controlling the application offluid pressure from the string into the cylinder on opposite sides ofthe piston, alternately, means on the cylinder 'engageable with thewalls of the well and adapted to allow only upward movement of thecylinder, said cylinder having fluidpassageways at its ends, valvesarranged to control the cylinder passageways and means for reversing theposition of said valves when the piston reaches the limit of itsmovement in either direction.

8.. A fishing-tool comprising, a tubular operating string of pipeincluding a'mandrel, means on works and which forms a closed chamberabout the lower end of the mandrel for engaging an object stuck in awell, a cylinder through which the mandrel works and forming a closedchamher about the mandrel, a piston on the mandrel and fitted in thecylinder, means for controlling the application of fluid pressure fromthe string into the cylinder on opposite sides of the piston,

alternately, slips on the cylinder engageable,

when in active position, with the walls of the well and adapted to allowonly upward movement of the cylinder, means initially retaining saidwall engaging means in inactive position to allow the tool to be loweredinto the well, said retaining means being releasable upon initialapplication of said fluid pressure to allow said engaging means to moveto active position, said cylinder having fluid passageways at its ends,valves arranged to control the cylinder passageways and means forreversing the position of said valves when the piston reaches the limitof its movement in either direction.

JAMES A. ARMITAGE.

No references cited.

